Steam iron



Sept. 10, 1963 s. R. BRCKER ETAL STEAM IRON l Filed MalOh 20, 1962 'y/a6 l 4e I4 Z; t g 'a7 l FI[\| o '9 l 8 1Q 2| w 23 3 l an D. 5m; Iz

United States Patent O 3,103,079 STEAM IRON Samuel R. Bricker, Shelby,and Alan D. Smith, Mansfield, Ohio, assignors to Westinghouse ElectricCorporation, East Pittsburgh, Pa., a corporation of Pennsylvania FiledMar. 20, 1962, Ser. No. 181,056 3 Claims. (Cl. 3877) This inventionrelates to steam irons of the flash type, more particularly to such aniron in which the reservoir for water is not in free or unrestrictedcommunication directly with the atmosphere.

The object of the invention is to provide as uniform as possible .flowof water yfrom the reservoir to the steam generating chamber, andconsequent uniform rate of steam generation, under the varyingconditions encountered by the steam iron, including the ironing positionin which the discharge of steam from the ports is restricted by thematerial being ironed, and the raised position of the iron in which itsteams freely, and also the various levels of water in the reservoir.

A further and more particular object is to provide such uniformity ofwater ilow and steam generation using a valve orice or opening of apractical size, such as .032 to .035 of an inch diameter, to control theflow of water from the reservoir to the steam generating chamber.

In many dash-type steam irons, an electrically heated steam generatingchamber is provided in the soleplate of the iron and water is fedthereto by gravity from a reservoir above the steam generating chamber.A drip valve controls this tlow of water to the steam generatingchamber, and the ilow passage is of suthciently small diameter to limitthe iiow to separate and intermittent droplets, each droplet Aflashingto steam as it hits the hot bottom of the steam generating chamber.

To prevent water in the reservoir splashing out through the till openingof the reservoir during ironing, it is common practice to provide a fillvalve which completely closes the 4till opening during ironingoperations. This necessitates the provision of a vent tube to permitentry of air to the reservoir to replace the water as the latter isgradually fed to the steam generating chamber.

It is desirable that the valve flow passage or opening be of a largeenough diameter that it can be machined accurately in a practicalmanner, and also that it does not clog readily. An opening of .032 to.035 of an inch diameter has been found satisfactory for these purposes.However, upon using an opening of this large diameter with a vent tubecommunicating at its upper end with the water reservoir and at its lowerend directly with the steam generating chamber, it was found that the owof water was excessive, presumably because of the high steam pressurecommunicated through the vent tube from the steam generating chamber tothe water reservoir.

In accordance with the present invention, this vent tube, or pressureequalizing tube as it is sometimes referred to, provides communicationbetween a region at the top of the reservoir above the water leveltherein, and a region of a steam flow passage connecting the steamgenerating chamber with a plurality of orifices in the bottom of thesoleplate, which orifices discharge steam, generated in the chamber, tothe material being ironed. This region of the steam flow passage withwhich the vent tube communicates is somewhat upstream of the dischargeorifices, but closer to the latter than to the steam generating chamber.Particularly, this region is one where the maximum steam pressure iscloser to that which occurs adjacent the inlets to the orices than tothat which occurs in the steam generating chamber.

3,103,079 Patented Sept. 10, 1963 With the above arrangement, both themaximum pressure and the average pressure in the reservoir above thebody of water therein will be less than the corresponding pressures inthe steam Igenerating chamber. The pressure in the steam generatingchamber is imposed on the under side of the drip valve, resistinggravitational ilow of Water therethrough, and since this pressure isgreater than the pressure in the reservoir above the water, the wateriiow rate through -the drip valve is less than it would be ifgravitational forces only were involved. Thus, the desired lflow iseffected without undesirable restriction of the ilow passage through thedrip valve.

In the general arrangement of parts herein illustrated, whicharrangement is popular today, the vent tube is relatively close to thesteam `generating chamber, due to the practice of locating the manuallyoperable elements of all the controls in the front post of the ironhandle. Consequently, the steam flow passage tends to be so short thatlittle pressure drop occurs between the steam generating chamber and theentrance to the steam discharge orifices, unless a special restrictionis provided in accordance with the present invention. As illustrated,one or more bai-lies or walls are interposed in the steam ow passage,increasing the effective length thereof and/ or providing one or morerestrictions, thus producing an additional pressure drop.

The invention and the advantages thereof will be apparent from thefollowing description and claims taken in connection with theaccompanying drawing, forming a part of this application, in which:

FIG. l is a `'fragmentary side elevational view, partially in section,of an iron constructed in accordance with the present invention; FIG. 2is a transverse sectional view, taken along the lines II-Il of FIG. l,looking in the direction indicated by the arrows; and

FIG. 3 is a horizontal sectional View, taken along the lines III- Ill ofFIG. l, looking in the direction indicated by the arrows.

In the drawings, the reference character 10 indicates a steam iron ofthe flash type previously described and including a soleplate 11, areservoir 12 for water positioned in spaced overlying relation to thesoleplate, a shell 13 which, in cooperation with the soleplate, enclosesand houses the reservoir 12, and a handle member 14 including at least afront post 16. If desired, the handle may also include the usual rearpost, although the latter is not necessary in practicing the presentinvention.

The reservoir 12 has an uptstanding neck portion' 17 received in adownwardly facing recess `1S in the lower end of the front handle post16. The upper edge of the reservoir neck 17 is sealed, by any suitablelcompressible gasket 19, with respect to the flat downwardly-facingsurface 21 of the recess 18. An opening or passage 22 is provided in thehandle post 16, this passage opening throu-gh the surface 21, inwardlyof the sealing gasket 19, `and also opening outwardly at the front ofthe post 16. Consequently, when the iron is tilted to ian uprightposition, with the front portion of the passage 22 in a verticalposition, water may 'be poured through the passage 22 into the interiorof the reservoir 12. In order to prevent splashing of water from thereservoir out through the ll passa-ge 22 during use of the iron, thereis provided a closure kdisc 23 for closing the ll passage 22 under allconditions except actual lilling of the reservoir. This disc 23 isfreely movable longitudinally on and with respect to la valve rod 26extending vertically through the reservoir 12. However, the closurevalve disc 23 is biased into closing position against its seat, which isa portion of the dat wall 21 of the recess 18.

3 This biasing is effected by a compression spring 24 which surroundsthe valve rod Z6 below the disc and is maintained under compression =byengagement with a washer 25 fixed on the Irod 26.

The lower end of the rod 26 constitutes la closure valve whichcooperates with a valve seat 2S at the upper end of la flow passage 29`formed through an insert 31 which extends from above the bottom wall ofthe reservoir to and thro-ugh a cover plate 32 which overlies and iscemented to, or otherwise held in tight engagement with, the top of thesolepl'ate 11. The passage 29 provides for limited flow of water fromthe reservoir 12 to a steam generating chamber 33 formed in thesoleplate immediately Ibelow the passage 29. When' the valve 27 and itsstem or rod 29 are in -a raised position, water passes intermittently tothe steam generating chamber 33 where it immediately ashes into steam.

An electric heating element 34, preferably of the sheathed type, isdisposed in the soleplate in close proximity to the steam generatingchamber, so that the bottom wall thereof is maintained at -asufficiently high ternperature to insure instantaneous flashing to steamof each ydrop of water as it falls thereonto from the reservoir. Aspreviously explained, the drip passage 29 is of suhciently smalldiameter that the water passes therethrough in separate and individualdrops, even when the valve is fully open.

As best shown in FIGS. 1 and 3, the cover plate 32 is provided with saplurality of downwardly-facing ribs or wall elements which are sealedagainst the top surface off the soleplate and cooperate therewith toprovide chambers and passages best shown in FIG. 3. From considerationof the latter figure, it will be apparent that the steam generatingchamber 33 is defined by, in addition to the cover plate and thesoleplate, an H-shaped'wall stnucture 35 and a V-shaped wall structure36, the two being spaced slightly to provide exits 37 for steamgenerated in the chamber. It will be apparent that these exits 37constitute restrictions in the path of flow of steam from the steamgenerating chamber 33 to a plurality of steam [discharge orifices 3Sprovided in the soleplate 11 and through which steam is dischargedthrough the bottom surf-ace of the soleplate to whatever material `isbeing ironed.

The flow path of steam from the generating chamber 33 to the orifices 38is indicated by the arrows in FIG. 3, and it will be apparent that afairly long fiow path is provided, even though the steam generatingchamber is relatively close to the exhaust or discharge orifices 38.This elongated passage arrangement may be desirable for the reasonspreviously discussed, particularly in irons of the type hereinillustnated, utilizing the presently popular arrangement Where themanual controls for the various valves are 'disposed in or at the frontpost of the handle. In many earlier iron designs, the control for thedrip valve was disposed in the space between the front and rear posts ofthe handle, and hence the drip valve, which was usually directly belowthe control valve, was disposed near or to the rear of the center of theiron, considered in la front-to-rear direction.

In order to prevent entry of water from the reservoir into the vent tube41, it is desirable to locate the upper end of this tube within the neck17 of the reservoir, where it is least likely to be subject `to theentry of Water due to movement of the iron during ironing. This resultsin the vent tube yand the drip valve being located in very closeproximity to each other, with the result that, were it not for theutilization of the present invention, the lower end of the vent tubewould receive steam at a pressure substantially the same as thatexisting in the ste-am generating chamber, with the result that thepressure in the upper portion of the reservoir would be substantiallyequalized with that in the steam generating chamber. However, aspreviously discussed, in order to have the 4 drip passage 29 of maximumdiameter, it is desirable to have the pressure above the water in thereservoir equalized with a pressure somewhat lower than that existing inthe steam generating chamber, and this result is produced -by the hereinillustrated invention.

Referring fagain to FIG. 3, it will be noted that the lower end of thevent tube 41 (indicated by the dotted line 41a in FIG. 3) extends into aregion 42 which is separated from the steam generating chamber 33 by theV-shaped wall structure 36. To further isolate the region 42 in whichthe lower end ofthe vent tube is located from the steam flowing to thedischarge orifices 38, a second V-shaped wall structure 43 is disposedin' somewhat spaced relation to the first-mentioned V-shaped wallstructure 36, with these two wall structures dispose-d lat oppositesides of the re-gion 42. v

A portion of the steam flowing to the exhaust orifices 38 passes betweenthese Wall structures 36 and 43, and passes under the latter throughgrooves or recesses 44 formed in the upper surface of the soleplate nearthe region 42.

It will be apparent that the lower end of the vent tube 41 is subjectedto a steam pressure which, while somewhat above that existing at theinlets to the exhaust orifices 38, is substantially below that existingin the steam generating chamber 33. Consequently, the upper portion ofthe reservoir 12, above the body of water therein, is likewise subjectedto this same pressure which is intermediate that in the steam generatingchamber and that at the discharge orifices.

The actual construction `and relationship of the fill opening closurevalve 23 Iand the drip valve 27 forms no part of the present invention,being disclosed and claimed in copending application Serial No. 179,357,filed March 13, 1962, and vassigned to the assignee of the presentapplication. However, it may be mentioned that there is provided, forvertical sliding movement in the front post 16 of the handle 14, a valveadjusting rod 46 whose upper end would be operatively associated with amanual adjusting or positioning member (not shown). The lower portion ofthis adjusting rod 46 carries a laterally-extending lug or arm 47 whichslidably receives the valve stem or rod 26 and, when raised from theposition shown in FIG. 1, engages the under side of a head l48 formed onthe valve Vstem 26 to raise the latter and its valve member 27 from thevalve seat 28 to open the drip Valve `and permit flow of water from thereservoir to the steam generating chamber.

When the adjusting rod 46 is moved downwardly from the position shown inFIG. l, its lower end will engage the disc closure valve 23 and tilt thelatter to open the valve for filling or emptying of the reservoir.

For a more detailed description of the construction and operation ofthese two valves, reference should be had to the previously-identifiedcopending application.

While the invention has been shown in but one form, it will be obviousto those skilled in the art that it is not so limited, but issusceptible of various changes and modications without departing fromthe spirit thereof.

We claim:

1. A steam iron including a soleplate having a steam generating chamber,

means for heating the soleplate in the region of said chamber,

a closed reservoir for w-ater above the soleplate,

means for supplying drops of Water from said reservoir to said chamberfor fiashing to steam therein, said soleplate having an orifice in thebottom surface thereof for discharge of steam, said iron having a firstpassage for liow of steam from said chamber to said discharge orifice,

means providing a second passage between the upper portion of theinterior of said reservoir and a region uml...

of said iirst passage where the pressure of the steam flowingtherethrough is less than maximum pressure in the chamber and greaterthan the maximum pressure at the orifice, and

baie means in said first passage separating the downstream portionthereof into a region communicating with the discharge orifice andanother region communicating with said `second passage.

2. A steam iron including a soleplate having a steam generating chamber,

means for heating the soleplate in the region of said chamber,

a closed reservoir for water above the soleplate,

means `for supplying water in droplet form from said reservoir to saidchamber for dashing to steam therein, said soleplate having an orificein the bottom surface thereof for discharge of steam, said iron having apassage for ow of steam from said chamber to said discharge orifice,

means defining a restriction in the iiow path of steam through saidpassage, and

means providing a pressure-equalizing passage between the upper portionof the interior of the reservoir and a region of said 4steam flowpassage downstream of the restriction therein.

3. A steam iron including a soleplate having a steam generating chamber,

means for heating said soieplate in the region of said chamber,

a reservoir for water above said soleplate,

a shell cooperating with said soleplateto house said reservoir,

a handle member including a front post mounted on said shell,

a drip valve positioned beneath said handle front post and providing forgravity iiow of water from said reservoir to said chamber for flashinginto steam` therein, t manually-operable means carried by said fron-tpost for controlling said drip valve, said soleplate having a pluralityof orices opening through the bottom surface thereof for discharge ofsteam to material being ironed, said iron having -a passage providingcommunication between said steam generating chamber and said dischargeorices,

a tube beneath said front post and near said drip valve providingcommunication between the upper portion of the interior of saidreservoir and a'region of said passage intermediate said chamber andsaid discharge orifices, and

means restricting said passage between said region thereof and saidchamber.

References Cited in the iile of this patent UNITED STATES PATENTSFinlayson et al June 30, 1959 Swenson ..V July 11, 1961

1. A STEAM IRON INCLUDING A SOLEPLATE HAVING A STEAM GENERATING CHAMBER,MEANS FOR HEATING THE SOLEPLATE IN THE REGION OF SAID CHAMBER, A CLOSEDRESERVOIR FOR WATER ABOVE THE SOLEPLATE, MEANS FOR SUPPLYING DROPS OFWATER FROM SAID RESERVOIR TO SAID CHAMBER FOR FLASHING TO STEAM THEREIN,SAID SOLEPLATE HAVING AN ORIFICE IN THE BOTTOM SURFACE THEREOF FORDISCHARGE OF STEAM, SAID IRON HAVING A FIRST PASSAGE FOR FLOW OF STEAMFROM SAID CHAMBER TO SAID DISCHARGE ORIFICE, MEANS PROVIDING A SECONDPASSAGE BETWEEN THE UPPER PORTION OF THE INTERIOR OF SAID RESERVOIR ANDA REGION OF SAID FIRST PASSAGE WHERE THE PRESSURE OF THE STEAM FLOWINGTHERETHROUGH IS LESS THAN MAXIMUM PRESSURE IN THE CHAMBER AND GREATERTHAN THE MAXIMUM PRESSURE AT THE ORIFICE, AND BAFFLE MEANS IN SAID FIRSTPASSAGE SEPARATING THE DOWNSTREAM PORTION THEREOF INTO A REGIONCOMMUNICATING WITH THE DISCHARGE ORIFICE AND ANOTHER REGIONCOMMUNICATING WITH SAID SECOND PASSAGE.